Currently upon successfull call to qemu's implementation of
virDomainSetBlockIoTune iotune settings are changed only for the
disk given in API if the disk is in iotune group while we need
to change the settings for all disks in the group.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Currently, if only iotune group name is given for some disk and
no any params then later start of domain will fail. I guess it
will be convenient to allow such configuration if there is
another disk in the same iotune group with iotune params set. The
meaning is that the first disk have same iotunes and the latter.
Thus one can easily add a disk to iotune group - just add group
name parameter and no need to copy all the params.

Also let's expand iotunes params in the described case so we don't
need to refer to another disk to know iotunes and this will make
logic in many places simple.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

And introduce virDomainBlockIoTuneInfoHasAny.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Also add a space before ending a comment.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

It is used by the user-alias handling code.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

Some *ParseXML functions have comments stating what kind of device
they parse with an outdated list of parameters, with the exception
of virDomainFSDefParseXML which claims to parse a disk.

Remove them, assuming the function names are descriptive enough.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

All the callees return either 0 or -1 so there is no need
for propagating the value. And we bail on the first error.

Remove the variable to make the function simpler.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

We have a helper variable to make the code more concise,
use it consistently.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

Now that the cleanup section is empty, eliminate the cleanup
label as well as the 'ret' variable.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

Use the g_auto macros wherever possible to eliminate the cleanup
section.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

Use the virXMLFormatElement helper to format the driver element
to simplify adding further sub-elements.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>

The template still references libvirt-qemu-shim, which was at one
point the name used to refer to what we now know as virt-qemu-run.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

A recent commit added an error check for too-nested backing chains
followed by a return, even though errors above jump to cleanup.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Fixes: b168fa88Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

Remove bogus G_GNUC_UNUSED attribute and add a missing space.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Fixes: d6006672Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

This will allow some testing before refactoring.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

The algorithm is used in two places to find the parent checkpoint object
which contains given disk and then uses data from the disk. Additionally
the code is written in a very non-obvious way. Factor out the lookup of
the disk into a function which also simplifies the callers.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

The function has no users now and there's no need for it as the common
pattern is to look up the whole disk object anyways.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

If a disk is unplugged and then the user tries to delete a checkpoint
the code would try to use NULL node name as it was not checked.

Fix this by fetching the whole disk definition object and verifying it
was found.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Lookup the whole disk definition rather than just the node name.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Upcoming patches will also use the domain disk definition. Rename disk
to chkdisk for clarity.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Upcoming patches will also use the domain disk definition. Rename disk
to chkdisk for clarity.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

qemuCheckpointDiscard is a massive function that can be separated into
smaller bits. Extract the part that actually modifies the disk from the
metadata handling.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Avoid two computations by using a boolean.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Test code will need to know whether the virQEMUCaps object contains any
machine types already. Add a helper and expose it via 'qemu_capspriv.h'.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

The previous approac of just purging the alias combined with the fact
that we filled in fake machine types in the test data meant that if a
test case used an alias machine type such as 'pc' or 'q35' it would not
properly resolve to the actual data returned by qemu.

This started to be a problem since the CPU driver now looks at the
default CPU reported with the machine type.

This patch replaces the original approach of just removing the alias by
replacing it with a copy of the machine type data which the type would
alias to. This means that we are using the real data while we don't
modify the test output after every qemu upgrade.

Additionally this change will allow us to drop adding the fake machine
types later.

The test fallout is from actually excercising the CPU driver with
actual data.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Separate out the internals as they will become more complex soon.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Every supported qemu is able to return the list of machine types it
supports so we can start validating it against that list. The advantage
is a better error message, and the change will also prevent having stale
test data.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Debian/Ubuntu linkers are more strict that other distros requiring glib
to be linked explicitly.

macOS needs -export-dynamic instead of -Wl,--export-dynamic
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Similarly to 510d154a we need to prevent
doing too deeply nested backing chains and reject them with a sane error
message.

Add a loop to go through the snapshots prior to attempting actually
creating them to prevent some possible inconsistent scenarios.

We don't need to do it when reusing backing chains as we'll be
re-detecting the backing chain in that case anyways.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Don't adopt the backing store data when reusing images provided by the
user. This will force a backing chain re-probe as users might have
passed in something unexpected in the overlay where our view of the
backing chain would not correspond.

This is done only for inactive snapshots as there we have way less
verification.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

The previous "QEMU shim" proof of concept was taking an approach of only
caring about initial spawning of the QEMU process. It was then
registered with the libvirtd daemon who took over management of it. The
intent was that later libvirtd would be refactored so that the shim
retained control over the QEMU monitor and libvirt just forwarded APIs
to each shim as needed. This forwarding of APIs would require quite alot
of significant refactoring of libvirtd to achieve.

This impl thus takes a quite different approach, explicitly deciding to
keep the VMs completely separate from those seen & managed by libvirtd.
Instead it uses the new "qemu:///embed" URI scheme to embed the entire
QEMU driver in the shim, running with a custom root directory.

Once the driver is initialization, the shim starts a VM and then waits
to shutdown automatically when QEMU shuts down, or should kill QEMU if
it is terminated itself. This ought to use the AUTO_DESTROY feature but
that is not yet available in embedded mode, so we rely on installing a
few signal handlers to gracefully kill QEMU. This isn't reliable if
we crash of course, but you can restart with the same root dir.

Note this program does not expose any way to manage the QEMU process,
since there's no RPC interface enabled. It merely starts the VM and
cleans up when the guest shuts down at the end. This program is
installed to /usr/bin/virt-qemu-run enabling direct use by end users.
Most use cases will probably want to integrate the concept directly
into their respective application codebases. This standalone binary
serves as a nice demo though, and also provides a way to measure
performance of the startup process quite simply.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

This enables support for running the secret driver embedded to the
calling application process using a URI:

   secret:///embed?root=/some/path

When using the embedded mode with a root=/var/tmp/embed, the
driver will use the following paths:

       configDir: /var/tmp/embed/etc/secrets
        stateDir: /var/tmp/embed/run/secrets

These are identical whether the embedded driver is privileged
or unprivileged.

This compares with the system instance which uses

       configDir: /etc/libvirt/secrets
        stateDir: /var/lib/libvirt/secrets

When an embedded instance of the secret driver is open, any other
embedded drivers will automatically use the embedded secret driver.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

This enables support for running QEMU embedded to the calling
application process using a URI:

   qemu:///embed?root=/some/path

Note that it is important to keep the path reasonably short to
avoid risk of hitting the limit on UNIX socket path names
which is 108 characters.

When using the embedded mode with a root=/var/tmp/embed, the
driver will use the following paths:

                logDir: /var/tmp/embed/log/qemu
           swtpmLogDir: /var/tmp/embed/log/swtpm
         configBaseDir: /var/tmp/embed/etc/qemu
              stateDir: /var/tmp/embed/run/qemu
         swtpmStateDir: /var/tmp/embed/run/swtpm
              cacheDir: /var/tmp/embed/cache/qemu
                libDir: /var/tmp/embed/lib/qemu
       swtpmStorageDir: /var/tmp/embed/lib/swtpm
 defaultTLSx509certdir: /var/tmp/embed/etc/pki/qemu

These are identical whether the embedded driver is privileged
or unprivileged.

This compares with the system instance which uses

                logDir: /var/log/libvirt/qemu
           swtpmLogDir: /var/log/swtpm/libvirt/qemu
         configBaseDir: /etc/libvirt/qemu
              stateDir: /run/libvirt/qemu
         swtpmStateDir: /run/libvirt/qemu/swtpm
              cacheDir: /var/cache/libvirt/qemu
                libDir: /var/lib/libvirt/qemu
       swtpmStorageDir: /var/lib/libvirt/swtpm
 defaultTLSx509certdir: /etc/pki/qemu

At this time all features present in the QEMU driver are available when
running in embedded mode, availability matching whether the embedded
driver is privileged or unprivileged.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The driver URI scheme:

  "$drivername:///embed?root=/some/path"

enables a new way to use the drivers by embedding them directly in the
calling process. To use this the process must have a thread running the
libvirt event loop. This URI will then cause libvirt to dynamically load
the driver module and call its global initialization function. This
syntax is applicable to any driver, but only those will have been
modified to support a custom root directory and embed URI path will
successfully open.

The application can now make normal libvirt API calls which are all
serviced in-process with no RPC layer involved.

It is required to specify an explicit root directory, and locks will be
acquired on this directory to avoid conflicting with another app that
might accidentally pick the same directory.

Use of '/' is not explicitly forbidden, but note that the file layout
used underneath the embedded driver root does not match the file
layout used by system/session mode drivers. So this cannot be used as
a backdoor to interact with, or fake, the system/session mode drivers.

Libvirt will create arbitrary files underneath this root directory. The
root directory can be kept untouched across connection open attempts if
the application needs persistence. The application is responsible for
purging everything underneath this root directory when finally no longer
required.

Even when a virt driver is used in embedded mode, it is still possible
for it to in turn use functionality that calls out to other secondary
drivers in libvirtd. For example an embedded instance of QEMU can open
the network, secret or storage drivers in the system libvirtd.

That said, the application would typically want to at least open an
embedded secret driver ("secret:///embed?root=/some/path"). Note that
multiple different embedded drivers can use the same root prefix and
co-operate just as they would inside a normal libvirtd daemon.

A key thing to note is that for this to work, the application that links
to libvirt *MUST* be built with -Wl,--export-dynamic to ensure that
symbols from libvirt.so are exported & thus available to the dynamically
loaded driver module. If libvirt.so itself was dynamically loaded then
RTLD_GLOBAL must be passed to dlopen().
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The intent here is to allow the virt drivers to be run directly embedded
in an arbitrary process without interfering with libvirtd. To achieve
this they need to store all their configuration & state in a separate
directory tree from the main system or session libvirtd instances.

This can be useful for doing testing of the virt drivers in "make check"
without interfering with the user's own libvirtd instances.

It can also be used for applications using KVM/QEMU as a piece of
infrastructure to build an service, rather than for general purpose
OS hosting. A long standing example is libguestfs, which would prefer
if its temporary VMs did show up in the main libvirtd VM list, because
this confuses apps such as OpenStack Nova. A more recent example would
be Kata which is using KVM as a technology to build containers.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

If a domain is configured to have an egl-headless display and a virtio
video device, virgl will be enabled automatically within the guest, even
if the video device is configured with accel3d='no'.

In this case we should explicitly pass 'virgl=off' to qemu.

See https://bugzilla.redhat.com/show_bug.cgi?id=1791236 for more
information.
Signed-off-by: NJonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>